ROCKS AND MINERALS Flashcards
• Study of minerals
• building blocks of rocks
• naturally occuring
• involves organic process — does not require living organisms
• chemically specific
Mineralogy
A scientist who studies and determines the physical and chemical properties of minerals.
Mineralogist
3 common rock forming minerals
• one of the most abundant minerals on Earth’s crust
• one of the original minerals present at the time of crustal rocks formation (solidification of molten material)
• an important mineral in determining classification of a rock
One common mineral that is found in ghe continental crust and contains felsic rocks
Plagioclase Feldspar 39%
Why is felsic rocks abundant than mafic?
Because continental crust is older and it piles up. Not unlike oceanic crust where it generates new crust from time to time.
Physical properties!!
• Color
• Streak
• Hardness
• Cleavage and fracture
• Crystalline structure
• Transparency and diaphaneity
• Magnetism
• Tenacity
• Luster
• Specific gravity
• easiest to identify
• more bright color means more pure and as concentrated in a particular material
Color
Streak
• colors of minerals in powder form
‼️Color may differ when pulverized
Hardness
• resistance to scratching
MOHS HARDNESS SCALE
1 = least hard: Talc = chalk
10 = most hard: Diamond
Cleavage and Fracture
• describes how the minerals break into pieces
Cleavage: flat surface smooth
Fracture: uneven, rough
Crystalline structure
• It is how atoms are arranged to form a mineral
• also known as crystal lattice
Transparency or diapheneity
• the degree to which light is transmitted through a mineral.
Magnetism
• the ability of mineral to attract or repel other materials.
Ex. Magnetite
Tenacity
• the ability of mineral to resists breakage
> Brittle - easy to break
> Malleable - easy to shape/flattened
> Elastic - stretchable
> Sectile - cut into sections
Ex. Diamond has low tenacity
Describes how the mineral appears to reflect light, and how brilliant or dull the mineral is.
Luster
• metallic - more reflection
Measures the density of a mineral
Higher concentration = more dense, high value
Less concentration = not so much
Specific gravity
Chemical property of Silicate Class and where can it be found
• SI04
• found in the continental crust
• Largest and most abundant
• Quartz (SI02)
Chemical property of carbonate class and where can it be found
- C03
- common underwater
- formed from dead bodies of marine organisms
- Calcite
Chemical property of sulphate class and where can it be commonly found
• S04 - Poly Atomic
• found where salty water slowly evaporates
• Gypsum (Cas0lO4 = 2H20)
Chemical property of Halide Class and where can it be commonly found?
- Halogens 7a
- contains natural salt which usually come from lakes, ponds
- Flourite
Chemical property of Oxide Class and where can it be commonly found
- O
- Hematite
Chemical property of sulphide
- S-² mono atomic
- Galena
Why are minerals important in the society?
• have a big component in the economic value
is the process of mineral extraction from a rock seam or ore –a natural rock or sediment containing one or more valuable mineral.
Mining
